Search results for "ADS"

showing 10 items of 1953 documents

Characterization of NOM

2015

Worldwide reports over the last few decades have shown that the amount of natural organic matter (NOM) in surface water is continuously increasing, which has an adverse effect on drinking water purification. For many practical and hygienic reasons, the presence of NOM in drinking water is undesirable. Various technologies have been proposed for NOM removal with varying degrees of success. The properties and amount of NOM, however, can significantly affect the process efficiency. To improve and optimize these processes, it is essential to characterize and quantify NOM at various points during purification and treatment. It is also important to be able to understand and predict the reactivity…

AdsorptionChemistryMultidimensional NMR TechniquesEnvironmental chemistryPortable water purificationWater treatmentMass spectrometryPyrolysisSurface waterFourier transform ion cyclotron resonance
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Confined But-2-ene catalytic isomerization inside H-ZSM-5 models: A DFT study

2015

The isomerization of cis-but-2-ene to trans-but-2-ene within a 22T H-ZSM-5 zeolite model, also in the presence of two adsorbed Pd atoms, has been studied by DFT calculations. The results obtained allow us to state that the cis/trans but-2-ene isomerization can easily proceed inside unsupported zeolite cavities. In this case, differently than in the gas phase reaction, the trans-but-2-ene is less stable than the cis-but-2-ene, when adsorbed on the zeolite inner surface. Excluding the adsorption-desorption steps, the isomerization process involves two intermediates and three transition states, whose energy content is always very low with respect to that of reagents and intermediate species. T…

AdsorptionChemistryReagentPhysical and Theoretical ChemistryZSM-5ZeolitePhotochemistryIsomerizationEne reactionTransition stateComputer Science ApplicationsCatalysiszeoliteIsomerization catalysis computational chemistry
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Gradual complement protein adsorption and macrophage polarization: inflammation & dental implants

2020

AdsorptionChemistrymedicineMacrophage polarizationInflammationOral Surgerymedicine.symptomComplement systemCell biologyClinical Oral Implants Research
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New adsorbents for thymidylate synthase affinity chromatography

1988

New affinity adsorbents, intended for chromatography of thymidylate synthase (EC 2.1.1.45) from different sources, consisting of p-[N-[(2-amino-4-hydroxy-6-quinazolinyl)-methyl]-N-2-propynylamino]benzoyl-γ-[α-(3-carboxypropylamino)]glutamyl-glutamyl immobilized either on macroporous copolymer of acrylonitrile and n-butyl acrylate or on macroporous polymer of acrylonitrile itself, both crosslinked with divinylbenzene and having aminoethyl groups, were obtained. Both adsorbents were found to be effective in dUMP-dependent binding of thymidylate synthase from regenerating rat liver.

AdsorptionChromatographyAffinity chromatographybiologyChemistrybiology.proteinGeneral ChemistryThymidylate synthaseCollection of Czechoslovak Chemical Communications
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Magnetic In-Tube Solid Phase Microextraction

2012

We report a new in-tube solid phase microextraction approach named magnetic in-tube solid phase microextraction, magnetic-IT-SPME. Magnetic-IT-SPME has been developed, taking advantage of magnetic microfluidic principles with the aim to improve extraction efficiency of IT-SPME systems. First, a magnetic hybrid material formed by Fe(3)O(4) nanoparticles supported on SiO(2) was synthesized and immobilized in the surface of a bared fused silica capillary column to obtain a magnetic adsorbent extraction phase. The capillary column was placed inside a magnetic coil that allowed the application of a variable magnetic field. Acetylsalicylic acid, acetaminophen, atenolol, diclofenac, and ibuprofen …

AdsorptionChromatographyChemistryElectromagnetic coilPhase (matter)Extraction (chemistry)MicrofluidicsAnalytical chemistrySolid phase extractionSolid-phase microextractionAnalytical ChemistryMagnetic fieldAnalytical Chemistry
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Study and Modelling of the Vacuum Swing Adsorption (VSA) Process Employed in the Production of Oxygen

1999

An isothermal and non-equilibrium mathematical model was provided for the multi-component adsorption process. In addition, the software was developed for the VSA-based production of oxygen with the use of a CaX zeolite molecular sieve. The mathematical model and computer software were verified on the basis of experimental data. The study employed a test stand comprising two adsorption columns. The adsorption pressure P A = 150 and 135 kPa and desorption pressure P D = 20 kPa were adopted in the experiments. The tests produced oxygen with the purity of 90–94% O 2 (vol), at an efficiency of 55–73% and productivity of 570–850 kg O 2 per ton per day. The calculation results showed good consiste…

AdsorptionChromatographyChemistryGeneral Chemical EngineeringDiffusionDesorptionAnalytical chemistrySorptionGeneral ChemistryVacuum swing adsorptionMolecular sieveZeoliteIsothermal processChemical Engineering Research and Design
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Zeolithe als Adsorbentien für die Trennung, Reinigung und Konzentrierung von organischen Wertprodukten in der präparativen Säulen-Flüssig-Chromatogra…

1995

AdsorptionChromatographyColumn chromatographyChemistryGeneral Chemical EngineeringGeneral ChemistryIndustrial and Manufacturing EngineeringChemie Ingenieur Technik
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Application of jäntti's method to volumetric adsorption measurements

2004

Jantti introduced a method to calculate the adsorption equilibrium by measuring the actual adsorbed amount three times after a change to the gas pressure. By this method the experimental time for adsorption measurement can be considerably shortened. The procedure was developed for use in adsorption measurements where the adsorbed masses are directly measured with a balance. In the present paper we will demonstrate that the method is particularly useful in volumetric (manometric) measurements.

AdsorptionGas pressureChemistryAdsorption equilibriumPhysical chemistryThermodynamicsSorptionPhysical and Theoretical ChemistryCondensed Matter PhysicsFast measurementJournal of Thermal Analysis and Calorimetry
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Mono- and Multi-Layers

2006

Thin films incorporating or consisting of calixarenes have been widely investigated. The capacity of such films to adsorb both ions and neutral species has engendered particular interest in their use in sensor devices. Semiconductors, non-linear optical and pyroelectric materials or switchable systems for data storage are further examples of their potential use [1]. Both monoand multi-layer films can be formed from calixarenes and resorcarenes, using a variety of techniques. This chapter deals with the fundamental basis of calixarene thin film applications, including film formation and characterisation as well as studies of selectivity in small molecule interactions. Real and potential appl…

AdsorptionMaterials scienceCalixareneMonolayerMoleculeQuartz crystal microbalanceNeutron reflectometryThin filmSelectivityCombinatorial chemistry
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Self-assembled titania-silica-sepiolite based nanocomposites for water decontamination

2009

WOS: 000264524200020

AdsorptionMaterials scienceNanocompositeChemical engineeringColloidal silicaSepioliteInorganic chemistryMaterials ChemistryPhotocatalysisNanoparticleGeneral ChemistryHuman decontaminationTitanium oxide
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